garbage collection

[allenb@cs.uoregon.edu]

I'm having a problem with some window functions that causes Lisp to start
garbage collection and continue until Lisp unexpectedly quits.  I have a
display window and a set of offscreen pixmaps with functions for moving images
back and forth between them.  I also have some functions for changing the
color look up tables.  Each of the offscreen pixmaps share a common color
table which is the one that is used to update the device color table.  I have
a function that allows me to compute and install various gradients of grey
scale.  This uses SetEntries to change the color table and works fine.  When
I try to use a different color table and do a SetEntries the garbage collection
starts.  Also, when I move values from another color table to the shared
color table and do a SetEntries the garbage collection also starts.  This
does not occur when I have no offscreen pixmaps.  Any ideas?  What can cause
this type of garbage collection behavior?

Allen